A new generation of optoelectronic devices such as organic thin film transistors (OTFTs), organic light emitting transistors (OLETs), organic light emitting diodes (OLEDs), printable circuits, organic photovoltaic (OPV) devices, electrochemical capacitors, and sensors are built upon organic semiconductors as their active components. To enable high device efficiencies such as large charge carrier mobilities (μ) needed for transistor/circuit operations, or efficient exciton formation/splitting that is necessary for OLED/OPV operations, it is desirable that both p-type and n-type organic semiconductor materials are available. Furthermore, these organic semiconductor-based devices should exhibit satisfactory stability in ambient conditions and should be processable in a cost-effective manner.
Several p- and n-channel molecular semiconductors have achieved acceptable device performance and stability. For example, OTFTs based on certain acenes, oligothiophenes (p-channel), and perylenes (n-channel) can exhibit carrier mobilities (μ's) greater than about 0.5 cm2/Vs in ambient conditions. However, molecular semiconductors typically are less easily processable than polymeric semiconductors, and often cannot be processed via printing methodologies due to solution viscosity requirements.
Accordingly, the art desires new polymeric semiconductors, particularly those having good stability, processing properties, and/or charge transport characteristics in ambient conditions.